550 maranello compression test result

1Mpa=145psi So all those numbers make no sense to me

 

What sort of mileage especially in the last year or two ? There have been comments in the past about compression test being compromised by slightly sticking valves often caused by lack of use (others may be able to describe this better than I) with the cure sometimes being suggested as the proverbial Italian tune-up

 

Thats a lousy compression test. One of the problems is so few anymore have an ability to interpret results. When I started in the business well over 40 years ago we did compression tests daily. Its done so seldom now might as well be a dog watching TV. Many testers have something like a green, yellow and red zone. The zones are based on standards of the 50's and should not be applied to farm tractors.
That is not a car I would be considering buying unless an overhaul was part of the picture.

 

I had compression test done on my 456 as a condition to buying. The old school way with a tester on each cylinder, I was present. I've always been told that the level is not that important, but all must be within +/- 10 pct. Mine was. Your picture looks worrying to me. Sorry

Is one bank OK, and the other might have head gasket issue? Mistimed cam belt? Valve adjustment gotten out of control? Just guessing of course

 

Hydraulic lifters, so adjustment not an issue. Not sure bad valve guides would show up on a compression test, but they would on a leak-down test.

 

If that's a pass what does it take to fail?

 

I would only buy it if either the issue was repaired as part of the deal, or I got it dirt cheap and was ready to do a major or part engine rebuild
The seller might hope for a buyer that doesn't insist on compression test

 

Maybe in Wonderland. Not in the real world.
Please explain how a timing belt causes uneven compression.

 

A. I didn't do the test. You are asking me over the internet what is wrong with your dog because he is not himself.
Do you really expect diagnostic work works that way?

B. Whats wrong with the motor? Its dead. All thats left to know is why. And you aint getting that on the internet.

 

Great idea. I have another. Why not get it diagnosed by a mechanic instead of a bunch of know nothing strangers on the internet?

 

If its a car you really want to pursue or believe an error was made, then If able, get another compression test done. Will they let you take it to another shop for your own PPI?

 

Nothing valid about it. Your understanding of how the engine works is far too basic to draw those conclusions.
Out of time cams effects every cylinder exactly equally.

That engine is junk. Quit looking for excuses to buy it.

 

This evolving thread makes me think about @Clyde Romero and his first 575.

Clyde unarguably has some of the most Maranello ownership miles experience amongst us….
He has surely had many many costly services with his 575 and Testarossa.

The man walked from his 575 and it looks like this car should also be walked from based on the info at hand.

I’ve personally “bought when I shouldn’t” and it was an expensive lesson on the black Project Talladega Racecar.

Good luck but I’d walk from this one….not enough “juice for the squeeze”….

 

I've been paranoid about the cam belt system since my 575 "ate" a bearing at 2 1/2 years of age and 10k miles. I think I was very lucky, IIRC, there were four ball remaining. It's had at least one bearing replaced at each belt service. Clyde's recent experience has increased my paranoia. Talked to my service person and he said belt issues and destroyed engines have been very rare in his experience, two, and both had belts more than ten years old.

 

What then is the statistical odds of Clyde having 2 identical failures on 2 cars so close in time?

If that bearing failure is rare then his experience back to backbmust be insanely rare?

 

"What then is the statistical odds of Clyde having 2 identical failures on 2 cars so close in time?"
******
I don't know, but it grabbed my attention. With this belt service, I'm having all of the bearing changed and replaced with Hill's.

 

Could not agree more. Next fall season when I do my belts again I'll be following the notes from Clyde's thread. 8-(

#ounceOfPrevention......

 

I think owning one of these cars is a great pleasure but requires an adjusted "mindset". A few weeks ago, I drove mine 350 miles for an oil change, general check and tighten hand brake cable. First issue leaking rear shock, no big deal until I did some research, next issue, sound from front of engine had changed over past few months, likely coming from oil pump chain....well if that needs attention then might as well do belts a year early and change all bearings, seals, gaskets, degree cam timing, etc., etc. Ten-fifteen years ago, cost estimate would have caused a WTF, now OK. The thought of buying one of the cars that hasn't been regularly serviced by competent people...would be a big no for me.